3/1/2010 Colloquium - William Bertozzi
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William BertozziMassachusetts Institute of Technology |
Event Info
Title: Nuclear Resonance Fluorescence and the Prevention of Nuclear Terror
Date: Mar 1, 2010
Location: 3105 Etcheverry Hall
Time: 4-5pm
Abstract
One component of the economic lifeblood of our nation resides in the transport of goods internationally and within our borders. For example, tens of millions of seagoing containers enter our country every year with minimal inspection and these provide an opportunity for accurate and reliable delivery of almost any quantity imaginable. In particular, they could be a delivery vehicle for explosives, toxic substances and weapons of mass destruction. One technique for examining such vehicles of delivery non-intrusively is Nuclear Resonance Fluorescence (NRF) which is capable of identifying almost any isotope through the unique signatures provided by the energies of excitation. Important examples are Special Nuclear Materials (SNM) such 235U and 239Pu. The physics of NRF will be discussed along with adjunct technologies such as effective-Z techniques and the detection of actinides via the energy spectrum of prompt neutrons from photon induced fission. NRF can provide signatures important in Nuclear Forensics helping to identify the origin of nuclear fuels, shielding and other relevant quantities important in the management of nuclear materials. Plans are for incorporating NRF systems in Nuclear Power plants and nuclear refinement facilities are presented as practical means to mitigate the purloining of SNM.
Speaker Biography
Professor Bertozzi is the principal investigator leading the Nuclear Interactions Group of the MIT Laboratory for Nuclear Science. The research program investigates the structure of nucleons and nuclei using high energy electrons and photons as probes. Experiments are performed at the accelerator facilities of the MIT Bates Linear Accelerator Center, the University of Mainz and the Thomas Jefferson National Accelerator Laboratory. The well understood electromagnetic interaction is used to determine the charge, current and magnetization responsible for reactions that lead to a better understanding of the forces between nucleons in a nucleus and the quarks in a nucleon.
Topics of study include:
1. The non-spherical components of the nucleon and non-central character of the force between the constituents of nucleons.
2. The origin of the spin or angular momentum of the nucleons.
3. The origin of the non-nucleonic components of the currents in nuclei.
4. The possible modification of the structure of nucleons in nuclei compared to the structure of free nucleons.
5. The structure of light nuclear systems and the testing of modern theoretical models of nuclei.
6. The short distance behavior of the force between nucleons in nuclei and other questions of topical and fundamental interest.
The unifying central theme of the research is the understanding of strongly interacting systems via the discovery of new phenomena and the comparison with modern theoretical models and concepts. The central goal is to determine the role played by quarks, mesons and nucleons in the making of nuclear and nucleon systems.
As part of the program, novel instrumental modalities are developed as needed. These have included particle detection and precision tracking, particle polarimetry, cryogenic targetry and particle spectrometry. In addition to Professor Bertozzi, the Nuclear Interactions Group includes approximately five Ph.D. research staff members and ten graduate students. The research is emphasized as an important component of graduate education. Undergraduate participation is encouraged.
